I’ve been scammed

[urbnkickzz]

I've sold a pair of Nike dunks to a buyer, everything was fine I provided proof of purchase and they went through eBay authentication fine as a success, and then the buyer opens a case claiming they are fake, I know he's trying to scam me and I've showed transactions from my bank account and ebay authenticating it and ebay are still siding with the scam artist of a buyer, any advice ?

[*guinevere*]

If you don't refund ebay will refund them out of your funds anyway, and tell the buyer to keep the trainers so you'll lose your money, the item, your selling fees, and get an account defect. 

Refund, and you can appeal later as Ruby Tuesday says, producing your proof of authenticity.